Ironically, I think Vulpera would be more interesting, even it's a goblin skeleton, at least it's aesthetically totally different than a goblin. A mechagnome is essentially just a metal gnome, it's a re-skin like mag'har, void, lightforged, etc. I really want allied races to steer more towards using the skeleton but having completely different aesthetics than just literal re-skins. That's why Zandalari and Kul'tirans are the ones people are looking forward to most. It's not just a paint job. I don't exactly want snake people personally, but at least it would be more unique to have than metal gnomes. Gnomes especially don't need a re-skin since they're the least played race IMO. Jinyu seem long overdue for alliance.
In Zul'Drak. Guys like Prophet of Sseratus, looks pretty much like an early version of Sethrak although with no legs, because legs doesn't make sense unless you're planning to make them an allied race and have armor pieces to worry about.